CIDR: The CIDR number describing the size for each basic network segment in the allocated range.

NetName: The network block name (chosen by the registrant I think).

NetHandle: The unique name (handle) with which the registration entry of that block is identified and organized within the whois database. The name "NET-70-84-0-0-1" shows that this is the first allocated block in the 70.84.x.x space.

Parent: For easier management the allocation entries are broken into levels for easier management within the database. In this case the zone with NetHandle "NET-70-0-0-0-0" logically contains all the alocations with NetHandle "NET-70-x-x-x-x".

NetType: Basically how this network block came to be allocated to the specific registrant. Direct Allocation plainly means that the registrant made an application for an address range to the proper sub-authority of IANA (i.e. ARIN), and was given a space that was previously free. There are certain possible nettypes, like "Direct Assignment", "Reassigned", "Reallocated", "IANA Special Use" and "IANA Reserved". This is related only to what predefined procedure was followed for the allocation of the specific address block (a purely internal organizational matter of IANA, so that allocations can submit to different policy rules). In IPv4 especially, it is important to avoid chaos because of the limited number of addresses.

Perhaps my descriptions are not completely accurate, the official ones should be somewhere in IANA's site.

PS. just a clarification, the result of this whois query doesn't show all the address ranges (blocks) a company owns, just how big is the block that the address you queried for belongs to, and what entity it is registered to.

Thanks a lot "nske", that was more like what i was looking for, but i am afraid i have many many more questions because there are still a lot of things which are unclear to me, is there any place where i can read more about these things ?

Next would be SP (Service Provider)
CCNA, CCNP (Switching), CCIE#20640

Well, as you must have guessed all these are bureaucratical policies that define how the allocation of public (Internet) addresses is done. So it basically concerns only those who wish to apply for a direct allocation of an IP address block (minimum /24 subnet) and it has nothing to do with anything technical. More like legal stuff..

The only good-to-know part is that ICANN (Internet Corporation For Assigned Names and Numbers) is the responsible authority to everything related to domain names and IP addresses in the Internet. [url=http://www.iana.org[/url]IANA[/url] (Internet Assigned Numbers Authority) is the sub-authority of ICANN that handles specifically the IP address allocations. In turn, IANA has delegated authority to a number of sub-authorities according to region: AfriNIC for Africa, APNIC for Asia, ARIN for North America, LACNIC for Latin America and RIPE for Europe. When you want to apply for the right to commit a range of Internet addresses, you deal with the proper sub-authority, according to your region. Each sub-authority has a little different procedures on it's own, which they are described in detail in their corresponding sites (i.e. see here for RIPE's policies and procedures), but they all follow the general lines described by IANA (like the existense of proper whois databases and servers for all the address allocations).

Same applies for the general whois databases information. You can i.e. read some information about the RIPE whois database here.